1. Field of the Invention
The present invention relates to packing bags and, more particularly, to an air packing bag having a film-type check valve in each of a plurality of air bladders thereof.
2. Description of Related Art
Conventionally, a plurality of small raised sacs are formed on a sheet of plastic so that an article enclosed in the sheet (i.e., served as packing bag) can be protected by the sacs. This packing bag can prevent the article from being damaged during shipping or storage. However, such small sacs can provide only a limited buffering effect to the article. Thus, the article may be damaged if the sheet is exposed to a significant impact.
Taiwanese Patent Publication No. 363,600 disclosed a packing bag comprising an inner surface, an outer curve surface, and an inflatable air bladder defined by the surfaces. Goods can be stored in the bladder prior to sealing. Such configuration can provide a buffering effect to the goods. Further, Taiwanese Patent Publication No. 128,326 disclosed an air packing sheet of plastic. The sheet is inflated prior to folding into two equal airtight bladders along a central seal for storing the goods therebetween. However, the bladders of both patents tend to puncture easily and leak air, resulting in failure of the buffering. Moreover, valves thereof are complex in construction, resulting in an uneconomic manufacturing cost.
Recently, an air packing bag including a plurality of parallel connected elongated bladders has become available in the market. Although such a packing bag can protect the goods stored therein, a number of drawbacks are found in it since all of the bladders are identical. For example, a seal between any two adjacent bladders may be not completely formed, resulting in a leak (i.e., low production). Further, alignment of seals is difficult, resulting in high manufacturing cost.
Therefore, it is desirable to provide a novel air packing bag having a film-type check valve in each of a plurality of air bladders thereof in order to mitigate and/or obviate the aforementioned problems.